1. Technical Field
The present invention relates to a wireless communication, and more particularly, to a method for performing mobility and an apparatus for the same.
2. Related Art
3rd generation partnership project (3GPP) long term evolution (LTE) is an improved version of a universal mobile telecommunication system (UMTS) and is introduced as the 3GPP release 8. The 3GPP LTE uses orthogonal frequency division multiple access (OFDMA) in a downlink, and uses single carrier-frequency division multiple access (SC-FDMA) in an uplink. The 3GPP LTE employs multiple input multiple output (MIMO) having up to four antennas. In recent years, there is an ongoing discussion on 3GPP LTE-advanced (LTE-A) that is an evolution of the 3GPP LTE.
A micro cell, a femto cell, and a pico cell, etc., having a small service area can be installed in a specific location of a macro cell having a wide coverage.
Due to mobility of a user equipment (UE) represented as a mobile device, quality of a currently provided service may deteriorate or a cell capable of providing a better service may be detected. Accordingly, the UE may move to a new cell, which is called performing of the mobility of the UE.
In order to perform the mobility, the UE persistently performs measurement on a serving cell and a neighboring cell. When the measurement result satisfies a condition for performing the mobility, the UE can receive an instruction from the serving cell and can directly perform the mobility.
There may be a cell which serves only a member UE allowed to access the cell. The cell may be referred as a Closed Subscriber Group (CSG) cell. In case that the target cell is the CSG cell, the UE checks whether itself is a member of the target cell in a mobility procedure. If only the UE is a member of the target cell, the UE can access to the corresponding cell.
In the above communication system, for supporting the mobility of the UE, cell identifying information may be provided, so as to make the UE distinguish a certain cell, i.e. a CSG cell, which allows a UE in a specific group. The cell identifying information may increase efficiency of the mobility performance of the UE, on the other hand may occur wrong mobility of the UE. Therefore, a method for efficiently and accurately performing the mobility in basis of the cell identifying information.